Catheter with side sheath

ABSTRACT

A catheter system for inserting a first guidewire in a primary vessel and a second guidewire in a branch vessel, comprising: a dual lumen catheter having a first guidewire slidably received within a first lumen; and a side sheath received within a second lumen; and a second guidewire slidably received within a lumen of the side sheath.  
     A method of aligning a side opening in a primary stent in registry with the ostium of a branch vessel, comprising: advancing a first guidewire through a primary vessel such that a distal end of a guidewire extends past an intersection of the primary vessel and the branch vessel; advancing the primary stent over the first guidewire with a dual lumen catheter, the dual lumen catheter having a side sheath received through a second lumen, and a first guidewire received through a first lumen; advancing the side sheath through the second lumen of the dual lumen catheter such that a distal end of the side sheath is positioned at the intersection of the primary vessel and the branch vessel; and advancing a second guidewire through the side sheath and out through the side opening in the primary stent and into the branch vessel, thereby aligning the side opening in the primary stent with the ostium of the branch vessel.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] The present invention is related to U.S. patent application Ser.Nos. 08/744,022, filed Nov. 4, 1996, now abandoned; 09/007,265, filedJan. 14, 1998; 08/935,383, filed Sep. 23, 1997; and 60/088,301, filedJun. 5, 1998; and PCT Patent Application No. PCT/US99/00835, filed Jan.14, 1999; the disclosures of which are incorporated herein by referencein their entirety for all purposes.

TECHNICAL FIELD

[0002] The present invention relates to catheter systems for deliveringstents.

BACKGROUND OF THE INVENTION

[0003] A type of endoprosthesis device, commonly referred to as a stent,may be placed or implanted within a vein, artery or other tubular bodyorgan for treating occlusions, stenoses, or aneurysms of a vessel byreinforcing the wall of the vessel or by expanding the vessel. Stentshave been used to treat dissections in blood vessel walls caused byballoon angioplasty of the coronary arteries as well as peripheralarteries and to improve angioplasty results by preventing elastic recoiland remodeling of the vessel wall. Two randomized multicenter trialshave recently shown a lower restenosis rate in stent treated coronaryarteries compared with balloon angioplasty alone (Serruys, P W et al.New England Journal of Medicine 331: 489-495, 1994, Fischman, D L et al.New England Journal of Medicine 331:496-501, 1994). Stents have beensuccessfully implanted in the urinary tract, the bile duct, theesophagus and the tracheo-bronchial tree to reinforce those body organs,as well as implanted into the neurovascular, peripheral vascular,coronary, cardiac, and renal systems, among others. The term “stent” asused in this Application is a device which is intraluminally implantedwithin bodily vessels to reinforce collapsing, dissected, partiallyoccluded, weakened, diseased or abnormally dilated or small segments ofa vessel wall.

[0004] One of the drawbacks of conventional stents is that they aregenerally produced in a straight tubular configuration. The use of suchstents to treat diseased vessels at or near a bifurcation (branch point)of a vessel may create a risk of compromising the degree of patency ofthe primary vessel and/or its branches, or the bifurcation point andalso limits the ability to insert a branch stent into the side branch ifthe result of treatment of the primary, or main, vessel is suboptimal.Suboptimal results may occur as a result of several mechanisms, such asdisplacing diseased tissue, plaque shifting, vessel spasm, dissectionwith or without intimal flaps, thrombosis, and embolism.

[0005] As described in related copending U.S. patent application Nos.08/744,022, filed Nov. 4, 1996, now abandoned; 09/007,265, filed Jan.14, 1998; 08/935,383, filed Sep. 23, 1997; and 60/088,301, filed Jun. 5,1998; and PCT Patent Application WO 99/00835, filed Jan. 14, 1998;systems have been developed for deploying a primary stent in a primaryvessel at the intersection of a primary vessel and a branch vessel witha branch stent extending into a branch vessel through a side opening inthe primary stent. Unfortunately, several difficulties exist whenattempting to position such an arrangement of a primary and branchstents at a vessel intersection.

[0006] For example, the insertion of separate guidewires into both theprimary vessel and the secondary vessel is required before positioning aprimary stent in a primary vessel with a branch stent projecting througha side opening in the primary stent into a branch vessel. Primary andbranch stents are then advanced over the separate guidewires which havebeen pre-guided one after another into the respective primary and branchvessels, such that the primary stent can be deployed within the primaryvessel and the branch stent can be deployed through the side opening inthe primary stent into the branch vessel. Unfortunately, when attemptingto guide two such separate guidewires through the primary vessel suchthat one enters the branch vessel, the two guidewires typically tend towrap around one another and become entangled. Additionally, time andeffort is required to individually position each of the two guidewiresone after another.

[0007] An additional disadvantage of conventional stents is thedifficulty in visualizing the stents during and after deployment, and ingeneral, the fact that they are not readily imaged by low-cost and easymethods, such as x-ray or ultrasound imaging.

SUMMARY OF THE INVENTION

[0008] The present invention comprises a dual lumen catheter systemhaving a guidewire received through the first lumen. A side sheath, (oralternatively, a second catheter), is slidably receivable within thesecond lumen of the dual lumen catheter. As will be explained, anadvantage of the present dual lumen catheter system is that it may beused for deploying a primary stent in a primary vessel and a branchstent in a branch vessel, wherein the branch stent is deployed throughan opening in the side of the primary stent with the side opening beingin registry with the ostium of the branch vessel. An advantage of thepresent dual lumen catheter system is that it avoids having toseparately position first and second guidewires within the respectiveprimary and branch vessels prior to deployment of primary and branchstents thereover. Rather, with the present invention, only a singleguidewire needs to initially be placed within the primary vessel, withthe present dual lumen catheter system subsequently deploying both theprimary and branch stents thereover.

[0009] The present invention also sets forth methods for aligning a sideopening of a primary stent in registry with the ostium of a branchvessel using the present dual lumen catheter system. In a preferredaspect of the method, a first guidewire is positioned within the primaryvessel such that a distal end of the first guidewire extends past aintersection of the primary vessel and the branch vessel. A primarystent is then advanced over the guidewire with the dual lumen catheter,wherein the first guidewire is received within a first lumen of thefirst catheter. The second lumen of the dual lumen catheter maypreferably be formed by attaching a side portion to the dual lumencatheter.

[0010] The second lumen of the dual lumen catheter is preferably formedfrom polyamide and lubricated on its inner surface with graphiteparticles to make its interior surface microscopically rough therebyreducing sliding friction when a side sheath or second catheter ispassed therethrough. Accordingly, the distal end of the side sheath,(which is received through the second lumen of the dual lumen catheter),can easily be slidably positioned to a desired location at theintersection of the primary and branch vessels such that the dual lumencatheter can be positioned at a desired location to deploy the primarystent within the primary vessel. After the distal end of the side sheathis positioned at the vessel intersection, a second guidewire can then beadvanced through the side sheath to pass out of the distal end of theside sheath, (passing through the side opening in the primary stent andinto the branch vessel), thereby aligning the side opening of theprimary stent in registry with the ostium of the branch vessel.Thereafter, the primary stent may be deployed within the primary vessel,such as by inflating a first balloon disposed over the first guidewireat a distal end of the dual lumen catheter.

[0011] The present invention also comprises a method of deliveringprimary and branch stents into the intersection of a primary vessel anda branch vessel such that a side opening in the primary stent ispositioned in registry with the ostium of the branch vessel, and suchthat the branch stent extends through the side opening in the primarystent and into the branch vessel. In a preferred aspect, this isaccomplished by deploying a primary stent within the primary vessel suchthat a side opening in the primary stent is registry with the ostium ofthe branch vessel with a second guidewire passing out through the sideopening in the primary stent and into the branch vessel as describedabove. A branch stent is then subsequently advanced over the secondguidewire and into the branch vessel such that the branch stent passesout through the side opening in the primary stent and into the branchvessel. The primary stent may optionally include radially expandableportions which protrude outwardly from the side opening in the primarystent and into the walls of the branch vessel, holding the side openingin registry with the ostium of the branch vessel.

[0012] To deploy the branch stent, the side sheath can be removed fromthe second lumen of the dual lumen catheter leaving the second guidewirein position in the branch vessel. In addition, the entire cathetersystem can be removed leaving the two guidewires in place such that thesecond catheter can be advanced over the second guidewire and into thebranch vessel. As such, the second catheter can then be advanced overthe second guide wire with its distal end extending into the branchvessel. A second balloon disposed over the second guidewire at a distalend of the second catheter can then be used to deploy the branch stentwithin the branch vessel. The branch stent may optionally comprise acontact portion at its proximal end to secure the proximal end of thebranch stent to the side opening in the primary stent.

[0013] In preferred aspects of the present invention, the distal end ofthe side sheath is positioned at the intersection of the primary vesseland the branch vessel by viewing its position under fluoroscopy. Also,in preferred aspects, the second guidewire is inserted through the sidesheath and into the branch vessel under fluoroscopic viewing.

[0014] The present invention also comprises an apparatus for aligning aside opening in a primary stent in registry with the ostium of thebranch vessel, comprising a dual lumen catheter system in which a firstguidewire is slidably received within a first lumen in the catheter anda side sheath is slidably received within the second lumen of the duallumen catheter. A second guidewire is slidably received within the lumenof the side sheath. To assist in guiding the second guidewire into thebranch vessel, the side sheath may preferably taper to a narrow distalend, which may be curved slightly outwardly and which preferablycomprises tungsten or other suitable radiopaque material such that itmay be fluoroscopically viewed. In other preferred aspects, a firstballoon is disposed over the first guidewire at a distal end of the duallumen catheter and a second balloon is disposed over the secondguidewire at a distal end of a second catheter which can be receivedwithin the second lumen of the dual lumen catheter.

[0015] Applications of the present system include the cardiac, coronary,renal, peripheral vascular, gastrointestinal, pulmonary, urinary andneurovascular systems and the brain. Further advantages of the presentdual lumen catheter system are that it provides an improved stentdelivery apparatus, which may deliver primary and branch stents to: 1)completely cover the bifurcation point of bifurcation vessels; 2) beused to treat lesions in one branch of a bifurcation while preservingaccess to the other branch for future treatment; 3) allow fordifferential sizing of the stents in a bifurcated stent apparatus evenafter a primary stent is implanted; 4) treat bifurcation lesions in abifurcated vessel where the branch vessel extends from the side of theprimary vessel; and 5) be marked with, or at least partly constructedof, material which is imageable by commonly used intraluminalcatheterization visualization techniques including but not limited toultrasound or x-ray.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1. is an illustration of a dual lumen catheter having a sidesheath slidably received within a second lumen of the dual lumencatheter.

[0017]FIG. 2. is an illustration of a dual lumen catheter having asecond catheter slidably received within a second lumen of the duallumen catheter, with balloons positioned on the distal ends of both ofthe dual lumen catheter and the second catheter.

[0018]FIG. 3 is an illustration of a placement of first guidewire withina primary vessel.

[0019]FIG. 4 is an illustration of the dual lumen catheter and sidesheath advanced over the first guidewire to a position where the sideopening in the primary stent is adjacent with the mouth of the branchvessel.

[0020]FIG. 5 is an illustration of the second guidewire as it isadvanced out of the distal end of the side sheath, through the sideopening in the primary stent and into the branch vessel.

[0021]FIG. 6 is an illustration of a branch stent of advanced over thesecond guidewire and through the side opening in the primary stent andinto the branch vessel by a second catheter received within the secondlumen of the dual lumen catheter.

[0022]FIG. 7 is an illustration of the deployment of the branch stent bya second balloon disposed over the second guidewire.

[0023]FIG. 8 is an illustration of the fully deployed primary and branchstents with the guidewires and dual lumen catheter removed.

[0024]FIG. 9 shows an embodiment of the present invention with radiallyexpandable portions around the side opening on the primary stent.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

[0025] The present invention comprises methods of aligning a sideopening in a primary stent in registry of the ostium of a branch vesseland methods for delivering primary and branch stents into anintersection of primary vessel and a branch vessel, such that the sideopening in the primary stent is in registry with the ostium of thebranch vessel with the branch stent extending through the side openingof the primary stent and into the branch vessel.

[0026] A novel catheter system is provided for accomplishing thepreferred methods. The present catheter system comprises a dual lumencatheter having a guidewire received through its first lumen. In oneaspect of the invention, a side sheath is slidably received through thesecond lumen of the dual lumen catheter. A second guidewire is receivedthrough the side sheath and the side sheath is positionable so as toalign a side hole in a primary stent with a branch vessel.

[0027] In an alternative aspect, a second catheter is slidably receivedthrough the second lumen of the dual lumen catheter. The second cathetermay optionally have a balloon disposed thereon such that first andsecond balloons are disposed over the dual lumen and second guidewiresat the distal ends of the respective dual lumen and second catheters,for deploying the primary and branch stents respectively.

[0028] Referring to FIG. 1, a catheter system 10 is provided comprisinga dual lumen catheter 12 and a side sheath 14, wherein side sheath 14 isslidably received within lumen 15 which may be formed as an extendingside portion of catheter 12 such that side sheath 14 can be axiallydisplaced with respect to catheter 12. The interior of lumen 15 ispreferably lubricated to reduce sliding friction with side sheath 14. Ina preferred aspect, the extending side portion of catheter 12 forminglumen 15 is fabricated of polyamide with graphite particles imbeddedtherein to yield a microscopically rough surface. Alternatively, theinner surface of lumen 15 may have metal powders, glass beads, Teflonpowder or other inorganic fillers imbedded therein.

[0029] As will be explained, an advantage of the present dual lumencatheter 12 is that catheter 12 can be positioned at a desired locationso as to align side hole 27 of primary stent 25 at the ostium of abranch vessel by positioning the distal end 16 of side sheath 14 at theostium of the branch vessel. Specifically, in a preferred aspect methodof using the present system, dual lumen catheter 12 can be positionedproximal the intersection of the primary and branch vessels to deploy aprimary stent in the primary vessel with side sheath 14 positioned atthe vessel intersection to deploy a second guidewire passing out througha side hole in a primary stent and into the branch vessel such that onlyone guidewire needs to initially be positioned within the primary vesselprior to subsequent deployment of the primary and branch stents.

[0030] As can be seen in FIG. 2, a second catheter 20 can be received inlumen 15. A balloon 11 disposed at the distal end of dual lumen catheter10 may be used to deploy a primary stent in a primary vessel. In thisaspect of the invention, side sheath 14 is preferably withdrawn overguidewire 31 after guide wire 31 is positioned in the branch vessel(FIG. 7). The second catheter 20 having a balloon 13 disposed at itsdistal end is then advanced over guide wire 31 with balloon 13 deployingan optional branch stent 40 as will be explained.

[0031] In a preferred aspect, the present invention is directed toaligning a side hole in a primary stent to a position in registry withthe ostium of a branch vessel. This first aspect of the invention isillustrated in the sequential steps shown in FIGS. 3 to 5.

[0032] In another preferred aspect, the present invention is directed todeploying a branch stent in a branch vessel with the branch stentextending into the branch vessel through a side opening in the primarystent. This second aspect of the present invention is illustrated in thesequential steps shown in FIGS. 6 and 7. (The sequential steps shown inFIGS. 6 and 7 are accomplished after the sequential steps shown in FIGS.3 to 5).

[0033] Referring first to FIG. 3, a first guidewire 21 is advancedthrough a primary vessel P in direction D such that distal end 22 ofguidewire 21 extends past the intersection of a primary vessel P and abranch vessel B.

[0034] As shown in FIG. 4, dual lumen catheter 12 is then advanced indirection D over guidewire 21 such that a primary stent 25, (which issupported at a distal end of catheter 10, as shown), is oriented suchthat side hole 27 of stent 25 is positioned generally adjacent the mouthof branch vessel B. (Guidewire 21 is received within a lumen in catheter10.) As can be seen, stent 25 is preferably crimped down onto sidesheath 14, as shown. Preferably, distal end 16 of catheter 14 hastungsten, or other suitable radiopaque material, deposited thereon suchthat it can be viewed and positioned fluoroscopically. Preferably, stent25 is initially crimped onto balloon 11 with distal end 16 of sidesheath 16 projecting outwardly through side opening 27 as shown. Assuch, fluoroscopic positioning of distal end 16 aligns side opening 27to branch vessel B, as dual lumen catheter 20 supporting stent 25 andside sheath 14 initially move together when stent 25 is initiallycrimped onto balloon 11.

[0035] As shown in FIG. 5, after distal end 16 of catheter 14 ispositioned as shown, a second guidewire 31 can then be advanced out ofdistal end 16 of side sheath 14, passing through side opening 27 instent 25 and into branch vessel B. As also shown in FIG. 5, balloon 11may be partially or fully inflated expanding stent 25 so as to providean access space for a distal end 26 of second catheter 20 to be advancedtherethrough, as will be explained.

[0036] As shown in the optional step of FIG. 9, balloon 13 on catheter14 can then be inflated to deploy radially expandable portions 29extending laterally outward from the edges of side opening 27, such thatportions 29 are pushed against the walls of branch vessel B, such thatside opening 27 is positioned in registry with the ostium of branchvessel B. Further description of such radially expandable portions 29which extend laterally outward from the edges of side opening 27 is setforth in Published PCT Patent Application WO 99/00835, filed Jan. 14,1998, incorporated herein by reference in its entirety.

[0037] In a second aspect of the present invention, additionalsequential steps, as illustrated in FIGS. 6 and 7, are instead carriedout after the steps illustrated in FIGS. 3 to 5 to deploy a branch stentin a branch vessel with the branch stent extending through a sideopening in the primary stent.

[0038]FIG. 6 is similar to FIG. 5, but side sheath 14 has been removedand a second catheter 20 has been advanced over guidewire 31 with abranch stent 40 disposed at distal end 26 of catheter 20. As shown inFIG. 6, distal end 26 of catheter 20 can be advanced over guidewire 31such that stent 40 is advanced through side hole 27 in stent 25 and ispositioned in branch vessel B.

[0039] As shown in FIG. 7, stent 40 can then be fully deployed withinbranch vessel B by inflating second balloon 13 disposed at distal end 26of catheter 20.

[0040] Primary stent 25 can be fully deployed by inflation of balloon 11either before, after or concurrently with branch stent 40 being deployedby inflation of balloon 13.

[0041] Lastly, as can be seen in FIG. 8, catheter system 10, (comprisingcatheter 12, catheter 20, and guidewires 21 and 31) can be removed afterdeployment of stents 25 and 40, leaving a bifurcated support at theintersection of primary vessel P and branch vessel B as shown.

[0042] As can also be seen, stent 40 may further comprise a contactportion 42 which remains disposed within side opening 27 therebysecuring the proximal end of stent 40 to side opening 27 of stent 25,thereby providing a bifurcated stent arrangement covering vesselintersection I.

What is claimed is:
 1. A method of aligning a side opening in a primarystent in registry with the ostium of a branch vessel, comprising:advancing a first guidewire through a primary vessel such that a distalend of a guidewire extends past an intersection of the primary vesseland the branch vessel; advancing the primary stent over the firstguidewire with a dual lumen catheter, wherein the first guidewire isreceived within a first lumen of the dual lumen catheter; positioning aside sheath received through the second lumen of the dual lumen cathetersuch that a distal end of the side sheath is positioned at theintersection of the primary vessel and the branch vessel; and advancinga second guidewire through the side sheath and out through the sideopening in the primary stent and into the branch vessel, therebyaligning the side opening in the primary stent with the ostium of thebranch vessel.
 2. The method of claim 1 , wherein, the primary stent isat least partially deployed within the primary vessel; and the distalend of a second catheter is then received within the at least partiallydeployed primary stent.
 3. The method of claim 1 , further comprising:deploying the primary stent within the primary vessel by inflating afirst balloon disposed on the dual lumen catheter over the firstguidewire.
 4. A method of delivering primary and branch stents into anintersection of a primary vessel and a branch vessel, such that a sideopening in the primary stent is in registry with the ostium of thebranch vessel and such that the branch stent passes through the sideopening in the primary stent and into the branch vessel, comprising: themethod of claim 1 , further comprising: advancing a branch stent overthe second guidewire and out through the side opening in the primarystent and into the branch vessel by a second catheter.
 5. The method ofclaim 4 , further comprising: deploying the branch stent within thebranch vessel by inflating a second balloon disposed on a secondcatheter over the second guidewire.
 6. The method of claim 1 , whereinpositioning the side sheath through the second lumen of the dual lumencatheter such that the distal end of the side sheath is positioned atthe intersection of the primary vessel and the branch vessel isaccomplished by: viewing the position of the distal end of the secondcatheter under fluoroscopy.
 7. The method of claim 1 , wherein advancinga second guidewire through the side sheath and into the branch vessel isaccomplished by: viewing the position of the distal end of the secondguidewire under fluoroscopy.
 8. A catheter system for inserting aprimary guidewire in a primary vessel and a side sheath in a branchvessel, comprising: a dual lumen catheter; a first guidewire slidablyreceived within a first lumen of the dual lumen catheter; a side sheathslidably received within the second lumen of the dual lumen catheter;and a second guidewire slidably received within a lumen of the sidesheath.
 9. A catheter system for inserting a primary guidewire in aprimary vessel and a side sheath in a branch vessel, comprising: a duallumen catheter; a first guidewire slidably received within a first lumenof the dual lumen catheter; a second catheter slidably received withinthe second lumen of the dual lumen catheter; and a second guidewireslidably received within a lumen of the second catheter.
 10. Theapparatus of claims 8 or 9, further comprising: a first balloon disposedat a distal end of the dual lumen catheter over the first guidewire. 11.The apparatus of claim 9 , further comprising: a second balloon disposedat a distal end of the second catheter over the second guidewire. 12.The apparatus of claim 8 , wherein, the side sheath tapers to a narrowdistal end.
 13. The apparatus of claim 8 , wherein, the distal end ofthe side sheath is fabricated from a fluoroscopically visible material.14. The apparatus of claims 8 or 9, wherein, the interior surface of thesecond lumen is lubricated with a coating of polyamide and graphite. 15.The apparatus of claims 8 or 9, wherein, the distal end of the secondguidewire is fluoroscopically visible.
 16. A kit comprising: anapparatus as in any of claims 8 to 14 ; and instructions for use settingforth a method as in any of claims 1 to 7 .